Metallic fastener



p 193.0. ROSENBERG 1,774,846

METALLIC .FASTENER Original Filed June 26, 1922 FW 4 i m Patented Sept. 2, 1930 PATENT OFFICE HEYMAN ROSENBERG, OF NEW YORK, N..Y.

METALLIC FASTENER Original application fllcd June 26, 1922, Serial No. 570,912. Divided and this application filed December.

22, 1923. Serial No. 682,269.

This invention relates to improvements in metallic fasteners, and more particularly to the type driven to fastening position, as, for example, as seen in my co-pending application for United States Letters Patent Serial No. 570,912, filed June 26, 1922, now Patent No. 1,545,471 issued July 7, 1925 of which this is a division.

The object in view is the production of an inexpensive fastener which .is characterized by its ease of application and effectiveness of anchorage.

With this and further objects in view as will in part hereinafter become apparent and in part be stated, the invention comprises certain novel constructions, combinations and arrangements ofparts as subsequently specified and claimed.

In the accompanying drawings,

tallic fastener embodying thefeatures of the present invention, the structure being shown on a magnified scale above the size of the average commercial fastener.

Figure 2 is a vertical, longitudinal section through a fragment of the fastener in the median plane of one of the projectionsya part of the material engaged being also seen in section, and the parts being shown on a still greater enlarged scale.

Figure 3 is a view in side elevation of a bar of stock which fasteners are to be made. Referring to the drawin s by numerals, 1 indicates a pin-like body aving a driving head 2, and being formed with integral projections 3, 3. Each projection 3 is formed from the material of the body 1, as-by being caused to flow into the outstanding position by the insertion of a pointed instrument into the material of body 1 to a position producing theopocket or recess 4 for each projection. The operation of punching outthe pro jections 3 on the body 1 is comparable with the formation of the projections on a large rasp. The projections 3 may be given various contours, according to the shape of the punchemployed and the extent to which it is forced into the metal of the body 1, it beingvpreferable to produce a projection of'the contour shown, which is provided Figure 1 is a view in side elevation of a me with a rounded under surface tapering in all directions from its greatest width and thickness downward to substantially a point at its lowerterminus and bending into the body 1. At the same time that the projection 3 is formed by the formation of the pocket 4, the projection is caused to have an upper edge or lip 6, which, in operation, functions .to prevent or retard any withdrawing movement of the body 1.

In operation, the material indicated at 5 in Figure 2 is formed with an aperture or recess of substantially the same transverse dimensions as the body 1, and as the lowermost projections 3 are spaced above the lower as end of body 1, such end is adapted to serve as a pilot and is inserted in the aperture or recess in the material 5.1 Then the head 3 is struck by an appropriate instrument for forcibly driving the body 1 into the material 5, notwithstanding the fact that the projections 3- overhang portions of the material 5. The projections 3 are hardened to a degree 'suflicient for entering metal, such as soft iron or soft steel, substantially without injury or effect upon the projections, and as the mate- 5,, rial 5 is of such soft metal, the drivingblows on the head 2 will cause the several projec tions 3 to enter the material 5 and form longitudinal channels therein. When the body 1 has been driven in as far as required, it will remain anchored because the flowing of the material 5, incident to the entry of the several projections 3 will cause the material to lap above the lips 6 of the several projections 3, as indicated in Fi re 2, whereby any attempted return or wlthdrawal movement of the body 1 will be resisted by engagement of the lips 6 with such overlapping material. The resulting action will be that the greater the pull exertedon the body 1 to withdraw it, the greater will-be the resistance up to the breaking point of the body 1'.

While the hardening of the projections 3 may be effected in any of various ways, it is preferable for convenience and avoidance of expense to accomplish such hardening by merely case-hardening the entire fastener, as

'by the usual cyanide process.

The present improved fastener is especially desirable as susceptible of being produced inexpensively by the process indicated in Figure 3, wherein is seen a rod of stock material which has been punched to produce theprojections 3 and on which is shown in dotted lines the outlines of the results of succeeding steps. The rod is cut at the cross lines 7 and then headed up to the condition shown in dotted lines at 2 in Figure 3, whereupon the fasteners are completed, except for the case-hardening process.

As clearly seen in Figure 2, the instrument employed for punching pockets 2 severs a minimum of material and flows the greater part of the material acted upon to the position seen. It is noted that this flowing operation includes outward movement of inte al portions of the body itself, so that the lower portion of each projection 3 has no part of pocket 4 inward of it. Thus the outstanding mass of material of body 1 (for approxi- 'mately or a little more than one-half of the length of each projection 3 and extending outward almost the maximum distance of the projection, as seen in Figure 2) is made of non-severed, solid, flowed portions of the material of the body 1. Such solid, outstanding portion, forming the lower entering end of each projection 3, and tapering in the direction of advance, functions first in acting on the material of work 5 to form the groove or path therein. Hence the maximum strain is received and sustained by the solid, outstanding body portion having no hollow at its back, and the part outward of the hollow or pocket 4 is relieved of the maximum stresses. Also, the hardened condition and the arched form of the portion outward of the hollow combine to enable it to effectively carry the strains to which it is subjected both in entering and in resisting withdrawal.

It is known to metallurgists and others skilled in the manufacture of metal articles that a rsw'edge of metal, such as produced by severance without kneading, rolling, annealing, swaging, or other finishing is comparable to a raw edge of cloth fabric, and just as the tailor turns a ham or works a buttonhole finish to preserve the raw'edge of a cloth fabric, it is particularly desirable to finish the raw edge of metal work if maximum strength, wearing capacity, and strain-resistance are to be provided. It is, therefore, important to note that in constructing the projections on the body of the pin in accordance with the present invention, raw or unfinished edges or surfaces-of metal are avoided by the kneading or annealing action incident to flowing'metal to form the projecttions and their pockets as distinguished from severing metal, such as would occur if the pockets were formed by a drill.

What is claimed is I 1. A metallic fastener comprising a pinlike body and a projection therefrom, the

'tion.

2. A metallic fastener comprising a pinlike body having an outstanding projection formed from the material of the body and the body having a pocket extending therein along the projection and oblique to the longitudinal axis of the body, that portion of the projection at substantially the transverse plane of the body'v represented, by the inner terminus of the pocket outstanding from the body as great or greater distance than any other part of the projection, andthe projection tapering thence to the body in the di-' rection of advance of the body when being driven into work. e

3. A fastener for metal work comprising a pinlike body having an outstanding projection and a pocket extending into the body along the projection and inclined inward and terminating short of the length of the projection. the projection being integral with the body and formed of solid mass between the body and the most outstanding portion of its work-engaging surface, thesaid workengaging surface tapering toward the entering end of the body and outstanding substantially the maximum distance outward of the projection within the limits of said solid mass.

4. A fastener for metal work comprising a pinlike body having an outstanding projection and a pocket extending into the body along the projection and inclined inward and terminating short of the length of the projection, the projection being integral with the body and formed of solid mass between the body and the most outstanding portion of its work-engaging surface, the said work-engaging surface tapering toward the entering end of the body and outstanding substantially the maximum distance within the limits of said solid mass, the said work-engaging surface being hardened sufficiently for entering metal, such as soft iron and soft steel, substantially without injury to such surface.

In testimony whereof I affix my signature.

HEYMAN ROSENBERG. 

